1

Cpu temperature monitor?

Jim Hibert

September 15, 2020 18:17

None

Follow

Is there a way to monitor the cpu temperature (RPI3B+ with Amp2)?  I have tried the usual suspects, but they aren’t included in the BuildRoot distro.   

thanks -

• Facebook
• Twitter
• LinkedIn

7 comments

• 0
  
  HiFiBerry team September 15, 2020 18:46

  You mean on HiFiBerryOS. You can use the /sys file system. However, there isn't really any need for this.

  Edited by HiFiBerry team September 15, 2020 18:47
• 0
  
  David C. Snyder October 02, 2020 20:47

  Jim Hibert - I found that this mostly did what I wanted:

  awk '{printf("- CPU temp : %.1f'"'"'C : %.1f'"'"'F\n", $1/1000, 32+($1/1000)*9/5)}' /sys/devices/virtual/thermal/thermal_zone0/temp
  
  - CPU temp : 60.1'C : 140.3'F

  I was curious since I just installed the new DAC2 HD on a Raspberry Pi 3 Model B and booted HiFiBerryOS. The metal case feels surprisingly warm when I place my hand over it. I like the look, feel, and functions of HiFiBerryOS, but I may switch back to DietPi to see if that yields lower CPU utilization and lower temperatures. This is unusually hot for this RPi3 model. My other RPi3 Model B with DAC+ Pro XLR and metal case stays around 44ºC.

• 0
  
  David C. Snyder October 02, 2020 23:05

  FWIW, I'm definitely seeing slightly lower temperatures with DietPi than I was with HiFiBerryOS. During playback:

  - CPU temp : 56.9'C : 134.5'F

  CPU idle time is higher as well…averages 97% while playing 32-bit, 192 kHz streams from Roon, and that probably accounts for the ~6º F drop in temperature. I don't consider the difference to be a big problem. HiFiBerryOS is the nicest looking webUI that I've ever seen on a Raspberry Pi audio component by a wide margin. I'll definitely be recommending it to friends.

  Since I'm a nerd, I'll probably continue to use DietPi on this thing to save a few degrees of temperature. In theory, lower CPU could contribute to slightly better sound, but I can't say that I hear an obvious difference. But, I'm glad that I gave HiFiBerryOS a try.

  

• 0
  
  HiFiBerry team October 03, 2020 05:25

  Why could a lower CPU temperature contribute to a better sound? CPU temperature does not have any impact on sound quality.

• 0
  
  David C. Snyder October 03, 2020 16:25

  Oh, for sure. Within reasonable bounds, CPU temperature does not matter. However, I've observed a correlation between low CPU utilization and sound quality. Theory is that the more busy a CPU is, the more RFI it emits. Some DACs are more affected by nearby RFI sources than others. Yours seem to be quite resilient; so folks can confidently use HiFiBerryOS with HiFiBerry DACs with no concerns.

  Oh, and I omitted a word in my previous post. It should have read:

  "In theory, lower CPU [utilization] could contribute to slightly better sound, but I can't say that I hear an obvious difference."

• 0
  
  Jim Hibert October 05, 2020 17:33

  Thanks, David. 
  
  

  looks like the meat is here:

  /sys/devices/virtual/thermal/thermal_zone0/temp

  I concluded the amp2 was overheating, since there was no output until I moved it and the pi back inside.  No long term damage. The pi kept serving up the HiFiBerryOS webpage, even in a watertight box,  in the direct So Cal sun, with 90 degree f ambient temp.
  
  

  just need to get the enclosure out of the direct sun.

   

• 0
  
  David C. Snyder October 05, 2020 18:17

  Yup. What numbers were you seeing before you moved it out of the sun?